Lint filter



I. E. MCWETHY Jan. 2, 1962 LINT FILTER 3 Sheets-Sheet 2 Filed July 18, 1960 INVENTOR. IRVIN E M WETHY ATTORNEY Jan. 2, 1962 l. E. MOWETHY 3,015,225

LINT FILTER Filed July 18, 1960 3 Sheets-Sheet 5 ATTCRNEY 64 66 5s 56 l I I FIGB INVENTOR. IRVlN-E-MWETHY i n Patented Jan. 2, T362 low drive shaft 28 which extends to a transmission, not 3,015,225 shown, such as that described in Flannery Patent 2,976,- LINT FlLTER llrvin E. McWethy, Syracuse, .35., assignor to The Murray Corporation of America, Syracuse, lJ.Y., a corpo= ration of Delaware Filed July 18, 1960, Ser. No. 43,421 6 Claims. (Ci. 68-18) This invention relates to washing machines, and more particularly to an agitator actuated lint filter therefor.

In washing machines of the vertical axis oscillating agitator type, the removal of lint from the wash tub during the wash period has been effected by circulating a portion or" the wash water continuously through a lint filter. In practice, the circulation has been eflfected by conduit means external, or separate from the wash tub with some form of pump for positively and continuously recirculating a portion of the wash water. In connection with such conduit means there is interposed a lint screen.

The present invention is directed to a lint filter which derives its recirculation direct from the action of the oscillating agitator upon the wash tub water, the invention taking advantage of the upward surge of wash water in the vicinity of the agitator column occurring as the agitator oscillates, the upsurge being received by an agitator supported annular lint filter adapted to continuously receive wash water directed thereinto from the upsurges resulting from the agitator oscillatory movement.

The invention is an improvement over that disclosed in application No. 32,429, filed May 27, 1960, wherein there is shown a lint filter especially applicable to an agitator of the spiral bladed type which during one half of each oscillation, produces a powerful upsurge of the wash water around the agitator column. More particularly the invention is directed to an improved annular construction capable of being quickly applied to the upper end of such an agitator, and adapted to employ the upper ends of the agitator blades to facilitate directing the up surge into an annular cup having an annular lint screening bottom. The invention more particularly comprises an annular skirt adapted to extend downwardly over the outer edges of the agitator blades, to a point below the normal wash water level, the skirt defining with the agitator, an annular passage way for confining and accelerating the upsurge produced by the oscillating agitator. The skirt is surrounded by an annular cup having a filter grid bottom disposed above the normal wash water level, and provision is made for directing the upsurge into the cup through suitable side. ports in the skirt.

The above and other novel features of the invention will appear more fully hereinafter from the following detailed description when taken in conjunction with the accompanying drawings. It is expressly understood that the drawings are employed for purposes of illustration only and are not designed as a definition of the limits of the invention, reference being had for this purpose to the appended claims.

In the drawings, wherein like reference characters indicate like parts:

FIGURE 1 is a vertical sectional view through a centrifugal extractor wash tub showing the agitator and filter mounted thereon.

FIGURE 2 is a plain view of the filter unit.

FIGURE 3 is a sectional view taken substantially on the broken line 3--3 of FIGURE 2; and

FIGURE 4 is a fragmentary sectional view of the unit mounted on the agitator, the section being taken through a discharge post.

In FIGURE 1 there is shown a centrifugal extraction tub 29 having overflow apertures 22 to establish a water level in the tub during washing. The tub is mounted on an annular plate 24 secured to the flange 26 of a hol- 746 issued March 28, 1961, the drive shaft being adapted to rotate the tub for centrifugal extraction during a part of the wash cycle.

Within the tub is an oscillating agitator 34} secured to the drive shaft 32 which also extends into the transmission. As is understood in the art, the agitator is oscillated through an angle of about 200 at a rate of about 60 oscillations a minute. The agitator 30 is secured upon the drive shaft 32 by a cap screw 34. The agitator comprises a hollow rigid column having a slightly tapered portion at its upper end as at 36, the column flaring at the bottom as at 38 to form the bottom skirt flange 4E}. The agitator has three integral blades ll which increase in radial width from top to bottom. Each of the blades at its upper end extends nearly vertically as atAZ and at its lower end each blade widens and extends spirally around the agitator column as at 46, terminating at its lower portion at the skirt flange periphery as at 44.

During the rotational portion of each cycle of movement of the agitator as it is rotating in the direction of arrow A, the blades tend to lift the water, producing an upsurge of wash water around the agitator column. In order to employ this upsurge during agitator oscillation for lint fiiltration, there is mounted upon the upper end of the agitator column, an annular filter unit indicated at 56!. The filter unit may comprise a unitary annular construction having an annular skirt portion 52 radially spaced from the agitator column and adapted to closely surround the outer edges of the three agitator blades 41. Integral with and surrounding the upper portion of the skirt, is an annular cup 50 having a perforate bottom wall 54 and an annular side wall 56. The cup bottom is provided with a lint filtering grid comprising a plurality of apertures 58. The skirt, at its upper end, is provided with an inwardly extending shallow flange or thickened collar portion 60, and the upper extreme end of the skirt 5'2 is provided with an inwardly extending annular head 62. The inside wall of the thickened portion 60 may be tapered slightly to fit against the tapered surface of the upper end of the agitator.

The thickened portion 60 is outwardly notched from the inside at three places as at 64 to receive the extreme upper ends of the three agitator blades 41. Adjacent each notch 64, the inner portion of the thickened portion is extended downwardly a short distance below the lower edge 66 of the thickened portion as at 68 and the external surface of such extended portion 68 is provided with an upwardly and outwardly curved deflecting surface 70. Radially aligned with the curved surface '70 is a rectangular aperture 72 to permit wash water surging upwardly within the flared skirt 52, to discharge into the annular space 55 defined by the cup. The inside wall of the skirt below the aperture 72 is cut away as at 74 to provide an adequate channel for the flow of water upwardly toward the aperture 72.

To accommodate a three bladed agitator, there are three apertures 72 disposed around the skirt 52, each aperture being adjacent a slot such as 64, adapted to receive the upper end of the agitator blade. It will thus be seen that adjacent each aperture 72, when the filter is placed upon the upper end of an agitator, there will be disposed an agitator blade which blade co-acts with the flarel skirt and the outer column wall of the agitator to provide a passage way for upsurging water to enter.

It will be understood that the passage way thus provided gradually diminishes in cross section as it extends upwardly toward the outlet aperture 72, and water upsurgiug therein will be accelerated and the upward flow de:

flected by the curved surface 70 and caused to flow outwardly through the apertures 72 and into the cup with each oscillation of the agitator.

The annular head 62 is adapted to be positioned immediately below an annular ridge '78 at the upper end of the agitator column. The filter will be made of a plastic such as polyethylene or polypropylene which has some elasticity or yield so that the filter unit may be placed upon the agitator column, the bead 62 being slightly distended to pass over the ridge '78 upon placing the unit upon or taking the unit from the agitator.

During the usual wash period the tub 2b is filled with wash water and detergent, and laundry. On each oscillation of the agitator, there is an upsurge of wash water within the filter skirt 52 and a substantial amount of Wash water is discharged through the apertures 72 into the cup annulus 55. The Water returns to the tub through the apertures 58, while the grid bottom 54 of the cup retains the lint. It will be seen that the cup bottom 54 is above the water level so that there is a continuous recirculation of wash water so long as there is agitator oscillation. It will also be seen that the flare of the skirt 52 is such that the upsurge of water is shielded from the cup bottom 54, the upsurging being caused to concentrate within the fiared skirt 52. The oscillatory movement of the cup causes the wash water to fiow annularly over the grid bottom 54, and thus lint is evenly built up over the entire annular apertured surface, and the full return of water to the tub is assured, through the grid apertures 58, it being evident that the lower edge of the apertures '72 is located sufficiently high above the cup bottom 54, to prevent reverse flow of wash water previously delivered to the annular cup during the interval between each upsurge.

At the close of the wash cycle, the lint may be readily removed from the cup bottom and disposed of, and the cup may be removed if desired by merely stretching the bead 62 slightly to clear the agitator ridges 78.

While a single modification of the invention has been illustrated and described, it is to be understood that the invention is not limited thereto. As various changes in the construction and arrangement may be made without departing from the spirit of the invention, as will be apparent to those skilled in the art, reference will be had to the appended claims for a definition of the limits of the invention.

What is claimed is: 1. A washing machine lint filter for an agitator of the oscillatory vertical axis type having a central column and the agitator, and extend to a point below the normal wash water level, said skirt having an inwardly directed collar adapted to embrace the upper end of the agitator column, and an annular integral cup disposed around the skirt having a lint filtering perforate bottom disposed above the normal wash water level, said collar being upwardly and outwardly notched to receive the upper ends of the blades of the agitator, and said skirt having a discharge aperture'adjacent each notch disposed above the perforate bottom of said cup, and means disposed radially inward of each of said apertures and adapted to abut the agitator column for deflecting wash water upsurging along the agitator column radially outward through said apertures.

2. A washing machine lint 'filter for an agitator of the oscillatory vertical axis type having a central column and integral agitator blades, comprising an integral structure form of resilient plastic and having an annular flared skirt adapted to overlie the upper ends of the blades of the agitator, and extend to a point below the normal wash water level, said skirt having an inwardly directed collar adapted to embrace the upper end of the agitator column,

and an annular integral cup disposed around the skirt having a lint filtering perforate bottom disposed above "the riormal wash water level, said collar being upwardly and outwardly notched to receive the upper ends of the blades of the agitator, and said skirt having a discharge aperture adjacent each notch disposed above the perforate bottom of said cup, means disposed radially inward of each of said apertures and adapted to abut the agitator column for deflecting wash water upsurging along the agitator column radially outward through said apertures and an annular head projecting inwardly from and adjacent the upper end of said collar, adapted to yieldingly pass over an annular ridge on the upper end of the agitator column to secure and position the filter axially upon the agitator.

3. In a washing machine, in combination, an agitator having a central column and a plurality of integral agitator blades each of gradually increasing width from top to bottom and extending generally parallel with the agitator column axis at their upper ends and extending spirally around the agitator at their lower ends, and a lint filter disposed upon the upper end of the agitator, said lint filter comprising an integral plastic annulus comprising an annular flared skirt adapted to overlie the agitator blades at their upper ends, and extend below the normal wash water level, and having an annular collar portion at its upper end adapted to yieldingly embrace the agitator column, said skirt having an integral surrounding annular cup hav ing a perforate lint filtering bottom disposed above the normal wash water level, and said skirt having a plurality of discharge apertures corresponding in number to the blades of the agitator disposed above the cup bottom, and means for angularly securing the lint filter upon the agitator column with each of the apertures adjacent the upper end of a respective blade, and above the spiral lower portion of each said blade.

4. In a washing machine, in combination, an agitator having a central column and a plurality of integral agitator blades each of gradually increasing width from top to bottom, and extending generally parallel with the agitator column axis at their upper ends and extending spirally around the agitator at their lower ends, a lint filter disposed upon the upper end of the agitator, said lint filter comprising an integral plastic annulus comprising an annular flared skirt adapted to overlie the agitator blades at their upper ends, and extend below the normal wash water level, and having an annular collar portion at its upper end adapted to yieldingly embrace the agitator column, said skirt having an integral surrounding annular cup having a perforate lint filtering bottom disposed above the normal wash water level, and said skirt having a plurality of discharge apertures corresponding in number to the blades of theagitator disposed-above the cup bottom, and means for angularly securing the lint filter upon the agitator column with each of the apertures adjacent the upper end of a respective blade, and above the spiral lower portion of each said blade, and means coacting between the upper end of said column and said collar for yieldingly securing and positioning said filter on said column.

5. A washing machine, comprising in combination a wash tub having means to establish a normal wash water level, a vertical agitator having a central column and a plurality of integral agitator blades each of gradually increasing width from top to bottom and extending generally parallel with the agitator column axis at their upper ends and extending spirally around the agitator at their lower ends, means to oscillate said agitator, and a lint filter disposed upon the upper end of the agitator, said lint filter comprising an integral plastic annulus comprising an annular flared skirt adapted to overlie the agitator blades at their upper ends, and extend below the normal wash water level, and having an annular collar portion at its upperend adapted to yieldingly embrace the agitator column, said skirt having an integral surrounding annular cup having a perforate lint filtering bottom disposed above the normal wash water level, and said skirt having a pluagitator column with each of the apertures adjacent the upper end of a respective blade, and above the spiral lower portion of each said blade.

6. A washing machine, comprising in combination a Wash tub having means to establish a normal Wash water level, a vertical agitator having a central column and a plurality of integral agitator blades each of gradually increasing width from top to bottom and extending generally parallel with the agitator column axis at their upper ends and extending spirally around the agitator at their lower ends, means ao oscillate said agitator, and a lint filter disposed upon the upper end of the agitator, said lint filter comprising an integral plastic annulus comprising an annular flared skirt adapted to overlie the agitator blades at their upper ends, and extend below the normal wash water level, and having an annular collar portion at its upper end adapted to yieldingly embrace the agitator column, said skirt having an integral surrounding annular cup having a perforate lint filtering bottom disposed above the normal wash water level, and said skirt having a plurality of discharge apertures corresponding in number to the blades of the agitator disposed above the cup bottom, means for angularly securing the lint filter upon the agitator column with each of the apertures adjacent the upper end of a respective blade, and above the spiral lower portion of each said blade, an annular ridge disposed about the upper end of said agitator column, and an inwardly projecting resilient head on said collar adapted to resiliently pass over said ridge and axially position said filter upon the agitator.

References Cited in the file of this patent UNITED STATES PATENTS 2,909,051 Altorfer Oct. 20, 1959 2,916,900 Gerhardt Dec. 15, 1959 2,942,444 Abresch June 28, 1960 

